An inkjet printing system, as one embodiment of a fluid ejection system, may include a printhead, an ink supply which supplies liquid ink to the printhead, and an electronic controller which controls the printhead. The printhead, as one embodiment of a fluid ejection device, ejects drops of ink through a plurality of nozzles or orifices and toward a print medium, such as a sheet of paper, so as to print onto the print medium. Typically, the orifices are arranged in one or more columns or arrays such that properly sequenced ejection of ink from the orifices causes characters or other images to be printed upon the print medium as the printhead and the print medium are moved relative to each other.
One type of printhead includes a piezoelectrically actuated printhead. The piezoelectrically actuated printhead includes a substrate defining a fluid chamber, a flexible membrane supported by the substrate over the fluid chamber, and an actuator provided on the flexible membrane. In one arrangement, the actuator includes a piezoelectric material which deforms when an electrical voltage is applied. As such, when the piezoelectric material deforms, the flexible membrane deflects thereby causing ejection of fluid from the fluid chamber and through an orifice or nozzle communicated with the fluid chamber.
One way to increase orifice or nozzle density or pitch is by reducing a width or distance between sidewalls of the fluid chamber. Reducing the width or distance between sidewalls of the fluid chamber, however, narrows the support for the flexible membrane thereby demanding an increased drive voltage for the actuator due to the greater stiffness of the flexible membrane. Thus, to operate the actuator with the same drive voltage, the flexible membrane is often made thinner. Making the flexible membrane thinner, however, increases strain on the flexible membrane near the sidewalls of the fluid chamber. For these and other reasons, there is a need for the present invention.